The present invention generally relates vehicle electrical systems and more particularly to an improved junction box assembly.
Modern vehicle electrical systems commonly employ junction box assemblies for distributing electric power between various wiring harnesses and electronic components, such as relays, microprocessors, diodes, transistors, capacitors, fuses and the like. Junction box assemblies are typically constructed so as to include a shroud for housing the connector ends of a plurality of wire harnesses, a junction box with a plurality of electrical terminals for electrically coupling the wire harnesses and electronic components, and a cover portion that substantially covers the base to inhibit water or other contaminants from contacting the electrical terminals and conducting electric power in an undesired manner. Despite the relatively widespread use of such junction box assemblies, the prior art junction box assemblies are known to have several drawbacks.
These drawbacks generally tend to be associated with the process of installing the junction box assemblies into vehicle in relatively high-volume, short cycle-time production lines. Modern high-volume vehicle manufacturing techniques favor the delivery of highly assembled modules or components to the vehicle assembly line so as to facilitate the efficient and reliable assembly of vehicles. In this regard, it is desired that all of the electrical components (e.g., fuses and relays) of the junction box assembly be secured such that they will not dislodge during transport and installation. Most of the various electrical components are configured to fit into recesses and positively engage electric terminals in the junction box and as such, there is little risk that these components will dislodge. Modern terminal fuses, however, are typically installed over the terminals of the junction box and are not typically fixed to the junction box until the cables (e.g., battery cables) have been coupled to the terminals. Accordingly, the installation of bladed terminal fuses to a junction box prior to the installation of the junction box to the vehicle has not been encouraged due to the relatively high risk that the terminal fuse will dislodge during transport and installation operations.
Another drawback relates to the coupling of cables to the various terminals. The known junction boxes are constructed such that the cables can rotate relative to the junction box when the cables are being secured to the terminals. Rotation of the cables relative to the junction box often shifts the cable into an undesired orientation that tends to stress the connection between the wires of the cable and the connector end.
A further drawback of the known junction box assemblies concerns the mating of the junction box to the shroud. Typically, snap-fittings, such as retaining tabs and retaining slots, are employed to fixedly but releasably couple the junction box and the shroud. The snap-fittings, however, are constructed such that the shroud and the junction box must be closely aligned to one another and all or a substantial portion of the retaining tabs engaged to the retaining slots simultaneously. Often times, however, assemblers find it relatively difficult to precisely align the shroud and the junction box such that all or a substantial portion of the retaining tabs engaged to the retaining slots simultaneously.
Yet another drawback relates to the coupling of the junction box to the wire harnesses that are disposed in the shroud. Modern junction box assemblies are typically configured such that the electrical contacts that extend from the junction box will engage mating electrical contacts in the connector end of the wire harnesses when the junction box and shroud are slid together. Unfortunately, junction boxes tend to be somewhat flexible and can bend when the contacts of the junction box and wire harnesses contact one another to thereby provide no electrical contact or an unreliable electrical contact therebetween. Some junction box assembly designs utilize threaded fasteners to draw the connector end and the junction box together to thereby promote the engagement of the electrical contacts. In some cases, however, the clamping force that is produced by the threaded fastener is insufficient to force the electrical contacts into engagement despite having tightened the fastener to a desired torque level.
Accordingly, there remains a need in the art for an improved junction box assembly that overcomes these and other drawbacks.
In one preferred form, the present invention provides a junction box assembly having a shroud, a junction box, a plurality of tab receiving slots and a plurality of alignment tabs. The junction box is configured to be received at least partially into the shroud. The tab receiving slots are formed into one of the shroud and the junction box. Each of the tab receiving slots defines an aperture with having a T-shaped cross section in a direction taken perpendicular to a longitudinal axis of the aperture. The alignment tabs are coupled to the other one of the shroud and the junction box and have a longitudinal axis, a stem and a flange. The stem and the flange are arranged such that a cross section taken through the alignment tab in a direction perpendicular to the longitudinal axis of the alignment tab is generally T-shaped and sized to fit in the aperture of a corresponding one of the tab receiving slots. The flange is tapered over at least one half of its length.
In another preferred form, the present invention provides an electrical junction box assembly having a junction box housing, a pair of terminals, a fuse and a clip structure. The terminals are coupled to the junction box housing and extend therefrom. Each of the terminals has a terminal post that is adapted for electrical connection to an associated cable assembly. The fuse is disposed over the terminals and is not fixedly coupled thereto. The fuse is configured to electrically couple the terminals when the cable assemblies are secured to the terminals. The clip structure is coupled to the junction box housing and engages the fuse to inhibit the fuse from disengaging the terminals when the cable assemblies are not coupled to the terminal posts.
In yet another preferred form, the present invention provides a junction box assembly having a shroud and a junction box. The shroud is configured for housing an end connector of a wire harness. The junction box is configured to be releasably coupled to the shroud and includes a junction box housing, a plurality of electrical contacts and a cue member. The junction box housing has a first side and a second side opposite the first side. The electrical contacts extending outwardly from the first side and are configured to engage a plurality of mating electrical contacts in the connector end. The electrical contacts are configured to be slidable relative to the mating electrical contacts between a disengaged condition and an engaged condition. The cue member is disposed in the junction box housing and slidable between a first condition and a second condition. The cue member slides from the first condition to the second condition in response to movement of the electrical contacts from the disengaged condition to the engaged condition such that the cue member extends outwardly from the second side to provide a visual indication of an electrical connection between the connector end and the junction box when the electrical contacts are in the engaged condition.
Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention.